Prospects for using boron in metallurgy. Report 2
The second part of the article presents perspective directions of using boron and its compounds in the preparation processes, metallurgical processing of ore materials and steel smelting in order to improve the quality of the final product. An efficient technology of silicothermal production of ferrosilicoboron containing 0.6 – 2.0 % B and 60 – 80 % Si has been developed. The advantage of this scheme is the possibility of obtaining a boron-containing alloy during ferrosilicon smelting. It has been experimentally shown that ferrosilicoboron has higher performance characteristics than ferroboron both in production and when used for steel processing. The results of industrial tests of the technology for microalloying pipe grades of steel with a new ferroalloy with boron confirmed a high degree of boron assimilation – up to 96 %. The possibility of widespread use of boron for steel microalloying is due to its cheapness, availability and environmental friendliness. According to the calculations, boron from complex ferrosilicoboron is the cheapest trace element used to increase the strength characteristics of steel. Additives of B2O3 can be successfully used to form high-magnesium liquid steel-making slags. It is shown that 0.37 – 0.55 % В2О3 effectively stabilizes the highly basic slags of the steel and ferroalloy industries. This operation allows obtaining a marketable lump material. The above review, results of the laboratory and industrial studies have shown the effectiveness of boron usage at different stages of metallurgical production. An increase in technical and economic indicators of production and quality of steel and ferroalloys, and effective disposal of waste slags is shown. The technical solutions advanced and tested at metallurgical enterprises do not require capital expenditures. They are implemented by adding microdosing of boron and its compounds to metallurgical production facilities.